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Author Topic:   Loosing oil pressure going into turn 3!
BrianW
Member
posted April 12, 2003 09:36 PM
Car is acting really odd... Engine is a 377, 6" rod, steel crank, gated oil pan, HV pump (anything else??) - anyhow - car ran great at practice nights, no problems - go for the first race this season and the oil pressure drops on entrance to turn 3 - light comes on at 15 PSI - I looked at the oil pressure gauge and it said ~12 PSI. get back on the throttle coming off of #4 and it goes up fairly quickly... Any thoughts?? I've heard things from over-oiling the top end (need restrictors), to changing oil brands, to cracked crank, or oil pickup is loose...

One more thing - when returning to the pits the light is off, the pressure reads about 38-40 PSI at 1000-1100 RPM idle, oil temp was 220* and water temp 180*

I'll be taking the pan off this week to check out the oil pan, pickup, clearances, but wanted to ask if anyone has an idea of what else I should be looking for???

Thanks in advance...
- Brian

[This message has been edited by BrianW (edited April 12, 2003).]

sdhnc29
Member
posted April 12, 2003 10:32 PM
Another thing that you might think about , if your running on a hooked up track and using a lot of rear break's , you can actually shut the engine down entering the corner and cause this problem . This might be your problem since you did not mention having this problem in turn 1 .

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


dirtrace54
Member
posted April 13, 2003 01:04 AM
I would agree with sdhnc29. I have never had that prob, but have heard others talkin about it. Sounds like everything else is workin great. Are you running on a d-shaped track? If you are, and the front stretch is the bow, both of the tight corners are on the back stretch. On a track like this, 3 would be where this prob is most likely to show up.


racer17j
Member
posted April 13, 2003 01:21 AM
sounds like the pick up tube to me had the same trouble last year


madmodshoe
Member
posted April 13, 2003 01:49 AM
We once had a piece of silicone that would sometimes be picked up the oil pump....
Have had an oil pan get slightly bowed by mud and partially block off the pickup....
Even had the pickup fall off of the pump....
But what takes the cake was a piece of aluminum that was loose that would crimp the oil pressure line to the gauge shut. All will drive you insane!


BrianW
Member
posted April 13, 2003 10:03 AM
OK - I know the engine isn't "stalling" when braking - as I'm getting back into the throttle through the corner when the light is still on...

I'm hoping that I'll find some trash in the pan or a loose pickup screen... Will let you know later this week..

racer17j
Member
posted April 13, 2003 10:06 AM
take a screwdriver and fish around in the pan before you go thru all the work of pulling it off and see if you can feal the pickup floating around in the pan


BrianW
Member
posted April 14, 2003 05:03 PM
racer17j - thanks for the tip - actually I've got a second reason for pulling it off -I want to check the bearing condition to make sure I haven't damaged anything yet and the rear main weeps a little and leaves a spot on the trailer floor - not much about a 1.5-2" spot, but enough to let me know it's leaking... Also gets the belhousing area splattered with a thin film - probably picky but I like a dry engine...


racer17j
Member
posted April 14, 2003 05:13 PM
hey don't blame ya a bit there but when your like me and you don't have anybody to help and pull motors with an old farm tractor you check every posibility to save work as you can lol


BrianW
Member
posted April 14, 2003 05:17 PM
Yep - that's the way it is... got to do a LOT of wrenching myself with no help... I think I can jack the car up and get the pan off without much effort (this is in a mod and the setback gets the crossmember out of the way...) - if I have to pull it I'll probably fish around first and maybe pull a valvecover and look at the condition up top..


BrianW
Member
posted April 15, 2003 09:53 PM
Well, got the pan off tonight and found the oil pickup lying in the bottom - going to pull the front bearing off and inspect just to make sure it's in good shape... If it is It'll be cleaned and bolted back together with Loctite this time! (blue good enough?)

Thanks for all the hints - I'm glad it was something simple this time

towmandan
Member
posted April 18, 2003 01:52 PM
A little extra insurance I usually tack weld the tube to the pump solves that problem...towman


BrianW
Member
posted April 18, 2003 03:12 PM
towmandan - this isn't a press-in pickup - this one is odd - it's a bolt on to the "face" of the pump where the pickup usually goes - Don't know if it's a big-block pump or what... It's got 2 bolts, one on each side of the pickup tube and a support tab that goes to the body of the pump. If it was a "standard" SBC pump with the pressed in pickup I would have tack-welded it too... It's almost like I need to safety wire this one if I have a problem with the Loctite holding.


towmandan
Member
posted April 19, 2003 01:23 AM
I havent ran into that one yet sorry I didnt help....towman


racer1030
Member
posted April 19, 2003 10:28 AM
Sounds like a Melling 10155 . Very good oil pump,gears supported at both ends,high volume.Use red loctite on pickup bolts.


BrianW
Member
posted April 19, 2003 04:07 PM
quote:
Originally posted by racer1030:
Sounds like a Melling 10155 . Very good oil pump,gears supported at both ends,high volume.Use red loctite on pickup bolts.

OK - where can I get a good pickup for the pump?? I guess call Melling?

The local place didn't know which one I had when I explained it to them - they usually deal in just the "regular" style pumps, and without taking it back out they couldn't tell me what it may be...



racer17j
Member
posted April 19, 2003 10:11 PM
look on midwestmotorsports,jr motorsports or speedway motors web sites they should have what your looking for


hamer36
Member
posted April 20, 2003 12:15 AM
Take off the pump cover and drill a 5/8" hole through the bottom bump where the oil channel is drilled. now plug and tack a 5/8" plug where the pickup goes. make sure you clean the pressure bypass of any metal. you can run it with hole open or put a short piece of pipe and screen (hose clamped) in the new oil entry hole.There is a pan co. that sells a pickup for this modification, it looks like a screened covered frost plug that you weld in, but i forgot the companies name. maybe canton?


66jj
Member
posted April 20, 2003 09:54 AM
last year i lost a pickup in a 100 lap lm race.

i pulled the pan replaced the pump, and looked at the brgs all looked good.

i lost the mains the next race..another 100, half way thru they started going.

my pressure went to 0 in the corner and stayed 0 till the flagstand on a tiny 1/4 mile paved track then it blasted to 70.

i decided if i lost another one and kept racing it, i would take it all apart, rather than taking a chance!!

just food for thought.

jeff

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